Excavator-bucket cleaner



.C. E. S TAHL. EXCAVATOR BUCKET CLEANER.

APPLICATION FILED SEPT, 23 I918- 1,336,595, Patented Apr. 13, 1920.

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wym g czamflwm C. E. STAHL. EXCAVATOR BUCKET CLEANER. APPLICATION-BLED SEPT 23, 1918.

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UNITED srnrns P TEN OFFICE.

CHARLES E. STAHL, OF WINIHBOI HARBOR, ILLINOIS, ASSIGNOR TO- FREDERICK AUSTIN, OF CHICAGO, ILLINOIS.

ExoAvaron-BUoKE'r CLEANER.

Specification 612 Letters Patent.

Patented Apr. 13, 1920.

Application filed September 23,1918. Serial No. 255,217.

To all whom it may concern:

Be it known that I, CHARLES E. STABL, a citizen of the United States of America, and a resident of Winthrop Harbor, Illinois, have invented a certain new and useful Improvement in Excavator-Bucket Cleaners,

I means for preventing breakage when the cleaner strikes a bucket or a load that fails to yield. It is also an ob ect to provide certain details and features of construction tending to insure the desired results,in a cleaner of this particular construction, and to render an excavator of this character less liable to of a portion of the cleaner mechanism.

- are carried. This is common and well' Fig. 4 is a detail section on line 4-4 in is thus illustrated, the invention oomprises a digging beam 1, of the usual or any suitable character and a casting 2 at the upper end thereo forming a bearing for the upper shaft 3, which carries the sprocket wheels 4 that o erate the endless sprocket chains 5 upon w ich the ordinary buckets 6 known construction in a trenching machine.

The cleaner arm 7 is pivoted at 8 on the upperend of the casting 2, and is pivotally connected at 9 with the upper end of the rod 10, which latter reciprocates up and down in a suitable bearing 11 on the casting 2, a spring 12 being applied to the rod below said bearing to yieldingly oppose by its compression the upward movement of the rod. The cleaner comprises a platel3 removably secured to the shank-14, which latter is pivoted or hinged at 15 upon the arm 7 ,the plate being thus disposed in position to pass through all of 'the buckets as the latter travel upward and over the sprocket wheels 4 at the top of the apparatus. The shank 14 has a lug 16, and a bolt 17 is inserted through this lug and the arm 7 for the purpose of rigidly securing the.

cleaner plate in position on the arm.

The bolt. 17 is of such character that it will break or will have its screw threads stripped, if the cleaner plate is accidentally struck by a displaced bucket, or by a load that does not yield, thus preventing break-1 age of the cleaner itself, or of the buckets.

A new bolt can then be inserted at small cost, thus restoring the machine to operative condition. 1 In this way the cleaner is characterized by a purposely weak point in the construction thereof, so that the cleaner can swingback on its pivot 15, as shown in dotted lines, in case the cleaner is struck'by under the strain of undue. pressure on the cleaner. It will be seen that the pivot 15 provides a normally inactive pivotal point between the cleaner 13 and the pivot 8 of the arm upon which the cleaner is sup-1 1 ported-that is to say, the. pivotal point 15 1s normally inoperative, so to speak, and does not function, but is brou ht into action b abnormal conditions in t e manner explained. The axis of the fulcrum or main pivot 8 extendshorizontally and this axis and the axis of the ivotal point 15 are parallel, so that the c eaner 13 has a normal swin ing movement about the axis 8, and an a normal or emergency swmgmg move- .ment about the pivot 15, thus preventing breakage, in the manner explained.

. What Iclaim as my invention is 1. In an excavator cleaner for scrapin out the loads from the buckets, a pivote arm, a joint forming a normally inactive pivotal point in said arm, a cleaner plate su ported thereb the axis of said oint belng parallel with the axis'about which said arm swings, a breaking connection to normally hold said joint rigid, adapted to release the joint and permit the cleaner plate to swing backward out of the way when struck by an unyielding object.

2. A structure as specified in claim 1, said breaking'connection comprising a bolt, and two portions through which the bolt is inserted, which portions are capable of relative pivotal movement when the bolt is broken or stripped by undue pressure on said cleaner plate.

3. A structure as specified in claim 1, said bearing connection comprising two portions held together by relatively weak means, adapted to separate when said means give way underthe strain of undue pressure on the cleaner plate.

4. The combination of the pivoted cleaner arm, the shank pivoted on said arm, spring means to control said-arm, so that the arm and shank have parallel axes, a cleaner plate secured to said shank, buckets to be cleaned by said cleaner plate, and relatively weak means to normally hold said shank rigidly in position on said arm, adapted to give way under the strain of undue pressure on the plate.

' CHARLES E. STAHL. 

